1. Field of the Invention
The present invention relates to a non-KSU (xe2x80x9ckey service unitxe2x80x9d) telephone apparatus, and more particularly to a non-KSU telephone apparatus and its method of operation within a non-KSU telephone system, which includes message recording in response to a transferred call, distributed message taking, and distribution and storage of CPID (calling party identification) information.
2. Background Information
Often small businesses and home offices that have multiple telephone lines simply connect individual telephone units and corresponding extensions to separate telephone lines. Generally, these consumers would find it advantageous to have the appearance of a larger organization. If the small business/home office experiences an increased volume of telephone traffic, one way of handling the increased volume is to upgrade the telephone system. Unfortunately, a telephone system such as a PBX system would be an impractical solution since avoiding major capital investments and service costs are important considerations for a small business/home office. A key telephone system obviates the need for a PBX system and attendant switchboard operators, since each telephone in the system is connected by a cable to a central control box referred to as a xe2x80x9ckey service unitxe2x80x9d (KSU). However, the necessity of special cabling complicates installation and creates difficult service problems should a break develop in one or more of the cables, or if the KSU itself should fail.
A distributed telephone system (one that does not require a central control box, e.g. no KSU required) which provides subscribers with system-wide features such as intercom and call transferring are known as xe2x80x9cnon-KSUxe2x80x9d or xe2x80x9cKSU-lessxe2x80x9d systems. These non-KSU systems are capable of significantly enhancing business efficiency and customer service in a cost-effective manner. However, the non-KSU systems do not include features that are found in KSU systems. For example, while call-transferring permits a person located at one station to manually transfer an incoming call to a person at a second station, traditional non-KSU systems are not able to transfer the incoming call from the first station and allow the incoming caller to record a message into a voice mailbox at the second station. In addition, non-KSU systems are not known to be able to be automatically answered (without human intervention) at one station and then allow the incoming caller to direct the call to a particular station within the system.
Furthermore, non-KSU systems are not known to have a decentralized answering system such that each station has its own telephone answering device. Generally, the cost of a centralized voice mail system varies depending on the number of stations the voice mail system is capable of handling. That is, a centralized voice mail system capable of handling 12 stations is generally more expensive than a centralized voice mail system only capable of handling three stations. Therefore, if the user only requires 2-3 stations as he is starting out, but he purchased a system capable of handling 12 stations, the cost of voice mail for these two or three stations would be accordingly more expensive. In addition, in centralized voice mail systems, users retrieve their messages by physically going to or dialing into a central station. It would be advantageous to have a non-KSU system with a distributed voice mail system in which each station is equipped with voice mail capabilities. Since the cost per station of a distributed voice mail system would remain constant, a user could start off with a small system and expand his telephone system as necessary. In addition, the user would have the ability to retrieve voice mail intended for a particular station, directly at that station without having to dial into a central station. Due to the lack of a distributed voice mail system, non-KSU systems are not known to associate calling party identification (CPID) information with their respective voice messages at the station to which the incoming call has been transferred.
There is also a need for a logical scheme for distributing and storing calling party identification (CPID) information. Generally all stations within a non-KSU system have access to all of the telephone lines. If the non-KSU system is capable of handling CPID information, every station would receive whatever CPID information is transmitted over every telephone line. In a known system, there are two settings which determine how CPID information is stored. Each station is set to either 1) store all the CPID information received over the connected telephone lines, regardless of whether it was intended for that station; or 2) only store the CPID information if the call is manually answered at that station. If the station is set for the second option and no one is there to answer the call, the CPID information is lost. It would be advantageous for CPID information to be stored at a directed station even if no one is there to answer the call at that moment. The first option provided by Nortel, whereby a station stores CPID information for every incoming call, would create information overload, thereby rendering the system extremely inefficient.
It is therefore an object of the present invention to provide an enhanced, cost-effective, and expandable non-KSU system.
It is another object of the present invention to provide a non-KSU system in which any station within the non-KSU system may be chosen to automatically answer incoming calls.
It is a further object of the present invention to provide a non-KSU system which prevents more than one station from automatically answering incoming calls.
It is yet another object of the present invention to provide a non-KSU system that allows for distributed recording of voice messages.
It is yet a further object of the present invention to provide a non-KSU system that allows transferred calls to be answered by a station""s voice mail.
It is still another object of the present invention to provide a non-KSU system in which the cost per station of having voice mail remains constant.
It is still a further object of the present invention to provide a non-KSU system that stores an incoming call""s calling party identification (CPID) information at a station if the incoming call is manually or automatically answered by that station.
It is still yet another object of the present invention to provide a non-KSU system that associates an incoming call""s CPID information with the respective voice message following the transfer of the incoming call to a destination station.
It is still yet a further object of the present invention to provide an apparatus that operates within a non-KSU system such that the apparatus may be selectively chosen to automatically answer incoming calls.
It is another object of the present invention to provide an apparatus that operates within a non-KSU system such that the apparatus has an integrated telephone answering machine.
It is further object of the present invention to provide an apparatus that operates within a non-KSU system such that the apparatus"" telephone answering device functionality is activated by signals other than central office (CO) ring signals.
In accordance with one form of the present invention, a non-key service unit (non-KSU) telephone apparatus for use with a plurality of telephones includes a line interface having an input operatively coupled to the plurality of telephone lines. The line interface also includes a plurality of outputs.
The non-KSU also includes a microcontroller operatively coupled to the line interface, a first multiplexer operatively coupled to the microcontroller and at least a portion of the plurality of outputs of the line interface, wherein the first multiplexer multiplexes transmit and receive audio signals for the plurality of telephone lines. The non-KSU also includes a coder/decoder coupled to the first multiplexer wherein the microcontroller instructs the first multiplexer to couple one of the plurality of telephone lines to the coder/decoder. The coder/decoder receives a telephone signal from one of the telephone lines, filters and compresses the telephone signal, and converts the filtered compressed telephone signal to a digital signal. The non-KSU also includes a digital signal processor operatively coupled to the coder/decoder and the microcontroller. The digital signal processor analyses the digital signal provided by the coder/decoder and determines whether the digital signal is a speech signal or DTMF tones. If the digital signal processor determines that the digital signal is DTMF tones, the digital signal processor decodes the DTMF tones and provides the decoded DTMF tones to the microcontroller, and if the digital signal processor determines that the digital signal is a speech signal, the digital signal processor compresses the digital signal and stores the compressed digital signal in a memory.
In accordance with another form of the present invention, a message transfer method for a telephone signal having a plurality of telephone lines and a plurality of telephone stations, one of which is designated as an audio-attendant station, includes the steps of:
receiving an incoming call from a caller on a first telephone line;
detecting a ring signal over the first telephone line at the telephone station that was designated to function as the auto-attendant station;
seizing the first telephone line via the auto-attendant station;
playing an outgoing message via the auto-attendant station on the first telephone line;
monitoring a response to the outgoing message by a caller on the first telephone line, the response corresponding to a desired one of the plurality of telephone stations that the caller would like the incoming call transferred to;
directing the incoming call via the auto-attendant station to a desired one of the plurality of telephone stations in accordance with the caller""s response;
encoding digital data which includes instructions on handling the incoming telephone call;
transmitting the digital data as a digital bit stream;
modulating the digital bit stream onto a telephone line shared commonly between at least the auto-attendant station and the desired telephone station, the digital bit stream containing information to specifically notify the desired one of the plurality of telephone stations to prepare to receive a transferred call and on which telephone line of the plurality of telephone lines the incoming call resides;
demodulating the modulated digital bit stream at the desired one of the plurality of telephone stations;
decoding the demodulated digital bit stream; and
generating a specific ring signal at the desired telephone station to indicate that a call is being transferred,
wherein if the transferred call is manually answered, the desired telephone station seizes the telephone line on which the transferred call resides, and
wherein in response to a drop in DC voltage when the desired telephone station seizes the telephone line, placing the auto-attendant station in an on-hook mode.
These and other objects, embodiments, features and advantages of this invention will be apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.